"Upon reflection, it seemed to me that those problems were quite serious."

And upon reflection, I think she was right to insist.

Upon reflection I think perhaps he had better go along with you.

Upon reflection, however, he decided the job "might be an opportunity to try out some ideas I had about community development and education."

Yet it seems to me upon reflection to be not so strange after all.

Perhaps there are no policies the nation has followed that we would want, upon reflection, to change.

Or perhaps it was not so curious, he thought upon further reflection.

But upon reflection I saw that this was not so.

Upon reflection, she admitted to herself that this would have been very difficult indeed.

She was, upon reflection, not in the least pleased to see him.